Nitration of anisol in dispersions of mesoporous oxides impregnated with heteropolyacids

Controlled nitration of anisole over HNO3/PO4/MoO3/SiO2/solvent systems

“…Apart from different nitrating mixtures, application of solid acid catalysts in anisole nitration were also described. Solid catalysts meet the recent ecological and safety requirements, and they can be promising alternative to commonly used catalysts [8][9][10][11][12][13]. For example, in the presence of acidic montmorillonite clay impregnated with anhydrous cupric nitrate, nitroanisoles with 98% yield were obtained [8].…”

“…Great selectivity to 4-nitroanisole (80%) was obtained in the reaction with P 2 O 5 /SiO 2 and fuming nitric acid [9]. Mesoporous silica impregnated with cesium exchanged Keggin type heteropolyacids (HPAs) were used as dispersed catalysts in the mixture of nitric acid (70%) and anisole [10]. The highest yield of nitroanisoles (ca.…”

“…So far, the catalysts combining catalytic properties of P 2 O 5 /SiO 2 (good selectivity [9]) with supported HPAs (high conversion and availability [10]) through mixing of phosphoric acid with ammonium molybdate, followed by impregnation of the obtained solution on the silica gel, and followed by heating, were successfully prepared. As a result, mixed catalysts composed of PO 4 3− ions built in the structure of surface Mo ∞ O 3∞ lattice (heteropolyanion-like species) were obtained.…”

Friedel–Crafts alkylation of sodium salicylate with 4-tert butylbenzyl chloride performed in aqueous dispersions of mesoporous oxides

“…These solvents are relatively expensive and have non-negligible toxicity [7][8][9]. It has previously been reported that a suspension of mesoporous oxide particles in an apolar medium is an environmentally attractive approach to the problem of reactant incompatibility [10][11][12]. The hydrophilic mesoporous particles are filled with an aqueous solution of the polar reactant and the surrounding apolar phase contains the apolar reactant.…”